Known in the art, there is the U.S. Pat. No. 5,107,657 of Werner K. DIEHL et al., granted on Apr. 28, 1992. In this patent, there is described an apparatus for wrapping a pallet load with a wrapping film applied selectively as a film rope or as a film sheet. A rotary arm support above the load B is arranged to be rotatably driven. A carriage which is mounted to an upright member, is arranged to be selectively driven along the upright member, either in an upward direction or in a downward direction.
Also known in the art, there is the U.S. Pat. No. 5,802,810 of John P. WOJCIK et al., granted on Sep. 8, 1998. In this patent, there is described a method and an apparatus for wrapping and securing film about a load. The film dispenser mounted on a rotary arm starts and stops the wrapping at a home lowered position.
Also known in the art, there is the U.S. Pat. No. 5,450,709 of Kurt L. STEDING, granted on Sep. 19, 1995. In this patent there is described a fully automatic stationary wrapping device having improved griping and cutting mechanisms. The device comprises a swing arm having a rotational circular motion and a swing arm carriage mounted and vertically displaced along a swing arm carriage support. With both circumferential and vertical displacement of the swing arm carriage, a helical wrapping pattern is produced on the stacked pallet. The wrapping starts with the swing arm carriage at its home position and ends with the swing arm carriage at the same home position. Then, the film is cut by melting.
Also known in the art, there is the U.S. Pat. No. 5,787,691 of Faruk M. TURFAN et al., granted on Aug. 4, 1998. In this patent, there is described an apparatus for wrapping articles in film material including a stationary frame supporting a vertically reciprocable frame which in turn supports a rotatable ring member carrying a film carriage assembly by which film is wrapped around a load during rotation of the ring member. The film carriage assembly is mounted on the ring member by means of a mounting bracket and, accordingly, is rotatable and vertically displaceable therewith.
Also known in the art, there are the following U.S. patents which describe different apparatuses and methods for wrapping articles:
U.S. Pat. No. 5,836,140 WRAPPING A LOAD WHILE CONTROLLING WRAP TENSION; PA0 U.S. Pat. No. 5,802,810 METHOD AND APPARATUS FOR WRAPPING AND SECURING STRECH FILM ABOUT A LOAD; PA0 U.S. Pat. No. 5,787,691 APPARATUS FOR WRAPPING ARTICLES IN PLASTIC FILM; PA0 U.S. Pat. No. 5,794,418 PALLET STRETCH WRAPPING MACHINE; PA0 U.S. Pat. No. 5,701,722 APPARATUS AND METHOD FOR PALLETIZING AND WRAPPING A LOAD; PA0 U.S. Pat. No. 5,628,167 METHOD AND APPARATUS FOR WRAPPING ELONGATE LOAD HAVING GENERALLY CIRCULAR OR GENERALLY ANNULAR ENDS; PA0 U.S. Pat. No. 5,623,808 APPARATUS AND METHOD FOR PALLETIZING AND WRAPPING A LOAD; PA0 U.S. Pat. No. 5,606,849 APPARATUS FOR WRAPPING A PACKAGE; PA0 U.S. Pat. No. 5,450,709 STATIONARY PALLET STRECH WRAPPING DEVICE HAVING IMPROVED METHOD AND APPARATUS FOR GRIPPING AND CUTTING OR WRAPPING FILM; PA0 U.S. Pat. No. 5,423,163 FREE STANDING PALLET WRAPPING APPARATUS; PA0 U.S. Pat. No. 5,408,808 AUTOMATIC FULL-WEB STRETCH-WRAPPING APPARATUS; PA0 U.S. Pat. No. 5,301,493 STEPLESSLY ADJUSTABLE PRE-STRETCHED FILM WRAPPING APPARATUS; PA0 U.S. Pat. No. 5,168,691 AUTOMATIC PLASTIC FILM WRAPPING MACHINE PARTICULARLY SUITABLE FOR SUITCASE; PA0 U.S. Pat. No. 5,107,657 WRAPPING APPARATUS AND RELATED WRAPPING METHODS; PA0 U.S. Pat. No. 5,054,263 METHOD AND APPARATUS FOR WRAPPING A PLASTIC FILM AROUND A LOAD; PA0 U.S. Pat. No. 5,005,335 STRETCH WRAPPING ROBOTIC PALLETIZER; PA0 U.S. Pat. No. 4,831,812 PROCESS AND APPRATUS FOR PASS-THROUGH WRAPPING; PA0 U.S. Pat. No. 4,691,497 FILM LAMINATION STRETCH WRAPPING; PA0 U.S. Pat. No. 4,631,898 PROCESS AND APPARATUS FOR CONTINUOUS WRAPPING OF PALLETIZED LOAD; PA0 U.S. Pat. No. 4,299,076 WRAPPING APPARATUS AND METHOD.
The drawback with all of the above-mentioned patents is that automatic machines have to wrap from bottom of the load to the top thereof, and then go back to the bottom to end its wrapping cycle. In that way, two layers of film are used to wrap the load. This results in a waste of film since sometimes only one layer of film in needed. This is also a time consuming operation since time is spent to wrap the second layer of film.
It is an objet of the present invention to provide a method and a wrapping machine that allows to start a wrapping cycle at any location along the load, and stop the wrapping operation also at any location along the load.
It is also an object of the present invention to provide a method and an wrapping machine for wrapping an article where it is possible to wrap the article with a single layer of film.
It is also an object of the present invention to provide a wrapping machine and a method to wrap an article where the wrapping of the article is faster than the method and apparatus of the prior art.